The rationale for conducting this study lies in the premise that if indeed the reason for a limited response of Kaposi's sarcoma lesions and other advanced malignancies to chemotherapy is attributable to a high expression of P-glycoprotein, then, by inhibiting this pump, tumor kill would be enhanced and response rates as well as duration of responses would also increase. Doxil is chosen since recent studies have shown that it is superior to combination chemotherapy with ABV or BV. Doxil is also known to be active in other malignancies such as breast and ovarian cancer (34,35). PSC 833 is chosen since it has been found to reverse P-gp in vitro and in vivo, is non-immunosuppressive, and has been shown in recent Phase 1 studies to be well tolerated.

There are yet no human studies reported on Doxil pharmacokinetics when combined with MDR modulators. Preclinical data shows that pharmacokinetics of Doxil, unlike free doxorubicin, is minimally affected by the addition of PSC 833 (36). Enhanced tumor toxicity was observed when PSC 833 was combined with Doxil. Since doxorubicin, the active agent in Doxil, is metabolized by the same cytochrome P450, interactions between these 2 agents may have very significant clinical implications. The purpose of this study is to assess the toxicity and determine the maximum tolerated dose of Doxil when combined with PSC 833 in the treatment of AIDS-KS and other advanced malignancies.

Patients will receive Doxil at the standard dose of 20 mg/m2 IV for the 1st cycle. On the 2nd cycle of Doxil, the first patient will receive Doxil at 40% of standard dose or 8 mg/m2 (dose level 1) IV over one hr. 15 mn after the 2nd and subsequent cycles of Doxil, PSC 833 will be given at 2 mg/kg for 2 hrs. Simultaneously, a 72 hour CIVI of PSC 833 will be started with the loading dose. If no DLT occurs, then a double dose escalation of Doxil (dose levels 3, 5, 7 ) will be given to the same patient in the subsequent cycles until DLT occurs. On the 2nd cycle, Doxil will be given at the next dose level above the starting dose tolerated by the first patient. If no DLT occurs, a double dose escalation will also be done for the subsequent cycles (dose levels 5, 7, 9). The single-patient-cohort will terminate when a patient experiences DLT or when two episodes of grade 2 toxicity occur. At that point patients will be enrolled into cohorts of 3 patients to determine the MTD.

Drug: pegylated liposomal doxorubicin hydrochloride

Other Name: DOXIL

Drug: PSC 833

Other Name: valspodar

Eligibility

Ages Eligible for Study:

18 Years and older

Genders Eligible for Study:

Both

Accepts Healthy Volunteers:

No

Criteria

INCLUSION CRITERIA

Histologically documented malignancy refractory to standard treatment or for which no standard treatment exists, or biopsy proven Kaposi's sarcoma with mucocutaneous lesions numbering 10 or more or a documented visceral KS lesion with at least 2 assessable cutaneous lesions.

Pregnant or breast feeding patients as radioactive tracer material and chemotherapy will be used in this protocol.

Active opportunistic infections requiring antibiotic treatment.

Treatment with radiation or electron beam therapy, interferon or cytotoxic therapy within the preceding 4 weeks.

Clinically significant history of congestive heart failure.

Patients who have moderate to severe sensory and motor peripheral neuropathy.

Any patient currently receiving treatment with any of the following agents which cannot be discontinued at a specified time relative to PSC 833 administration. All of these drugs are well substantiated to interact with cyclosporin A:

Agents increasing serum concentrations of CsA

The following drugs must not be administered for 48 hours before PSC 833 is started, during the course of its administration, or up to 48 hours after the last dose of PSC 833 in a cycle:

Any patient, who, in the judgment of the investigator, may not be able to complete this study.

Contacts and Locations

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00003207